<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <form oninput="c.value = parseInt(a.value) + parseInt(b.value)">
        <!-- 计算器 获取到每个输入框用户输入的值 -->
        <!-- 字符串类型=> 数字 数学计算 -->
        <input type="text" id="a">
            +
        <!-- <input type="text" id="b"> -->
       0 <input type="range" id="b" min="0" max="200">200
            = 
        <output name="c"></output>
    </form>
</body>
</html>
<!-- <script>
    a.onclick = function(){
        console.log(a.value)
    }
</script> -->
<!-- 
    - 输入框里面的值得获取到 dom结构.value
 -->
 <!-- 
     js + 表示字符串拼接
     parseInt() 将字符串类型转换成整型(数字)
  -->